Options for automate garden irrigation

My home is controlled by KNX and over this layer, I use HA for a more intelligent control. It works like a charm. Using knx, Now, I am working in the garden. I can control the irrigation valves using knx, but I would need to garden feedback about moisture, etc.

Could you recommend hygrometer devices for the garden that could be integrated in HA?

Also, is there a HA project that check the weather forecast to anticipate rain and to avoid irrigate?

Thanks

Hi,
Could you tell me what valves you are using and how they are connected/communicating with KNX or HA?

Regards Richard